Let someone deal with your LTT tax affairs
Letting someone act for you
The Welsh Revenue Authority gives two routes for someone to handle your LTT tax affairs.
- Give a person permission to act for you.
- Or provide evidence that you hold power of attorney.
Scroll down for the full analysis.
Read the original guidance here:
Let someone deal with your LTT tax affairs
You can let someone else deal with your Land Transaction Tax (LTT) affairs at the Welsh Revenue Authority. This can help if stamp duty paperwork feels hard to manage. Two routes are available through the authority: you can grant permission, or establish that you already hold power of attorney.
What this rule is about
Another person may need to speak on your behalf. That person might be a tax professional, friend or relative. Which route applies depends on their authority. It also depends on the authority they hold.
What the official source says
Official Welsh Revenue Authority guidance sets out two ways for somebody to act for another person in tax affairs.
- You can authorise someone to act for you.
- That person can be a tax professional, friend or relative.
- If you hold power of attorney, you can tell the authority.
- You must provide evidence of that power of attorney.
What this means in practice
Do not assume that a person helping with a property purchase can automatically deal with your LTT matters. To act for you, a person must show the authority why they are doing so.
- Choose the permission route if you want to appoint someone.
- Use the power of attorney route if you already hold that authority.
- Keep evidence ready where power of attorney is involved.
How to analyse it
The relationship helps identify the route. Next, match it to the route the official guidance describes.
- Ask who will contact the Welsh Revenue Authority.
- Check whether you are giving new permission.
- If not, check whether power of attorney already exists.
- Gather evidence if you rely on that power.
Example
Asha wants her brother to help with her LTT tax affairs. If he already holds power of attorney for Asha, he can tell the Welsh Revenue Authority and provide evidence instead, but if he does not, she can authorise him to act. These routes differ.
Why this can be difficult in practice
These are separate routes. They are not the same route in the official guidance. Official guidance does not say exactly which evidence it will accept, what each authority will cover, or how it will distinguish between them in practice. That remains unclear.
- A helper may need formal permission before speaking for you.
- Holding power of attorney does not remove the need to provide evidence.
- The required documents are not set out on this overview page.
Key takeaways
- You can authorise someone to deal with LTT tax affairs.
- A tax professional, friend or relative can be authorised.
- Power of attorney holders must provide evidence.
Technical analysis
For advisers, and for anyone who wants to check the law behind this page. You do not need this section to understand the guidance above.
Official guidance
The pages below are the Welsh Revenue Authority’s guidance. Guidance is not law. It sets out how the Welsh Revenue Authority reads the legislation, and it is not binding on you, on a tribunal or on a court. Where guidance and the legislation differ, the legislation wins. the Welsh Revenue Authority can also change or withdraw guidance, and it may not cover your facts.
Where this is not settled
- The source does not explain what evidence the Welsh Revenue Authority will require for a power of attorney.
- The source does not say whether permission covers every tax task or only selected matters.
Evidence you would need
This kind of case is decided on the facts of the individual property. These are the records that usually settle it, and the ones an adviser would ask you for.
- Any permission details requested by the Welsh Revenue Authority.
- Evidence that you hold power of attorney, where that is the route used.
Explore this with an AI
Readers often want to test their own situation. Copy the prompt below into ChatGPT, Claude or Gemini. It hands the model the actual legislation for this page rather than letting it answer from memory, and tells it to be explicit about what is uncertain. What comes back is information, not advice – check it against the links above.
I am researching Land Transaction Tax (LTT), the tax on property in Wales. It replaced Stamp Duty Land Tax in Wales on 1 April 2018, and SDLT does not apply in Wales. MY QUESTION Let someone deal with your LTT tax affairs [Replace this with your own situation: what you are buying, the price, the dates, who the buyer is, and what you plan to do with the property.] Guidance page from the Welsh Revenue Authority on this topic (guidance, not law): https://www.gov.wales/authority-to-act-welsh-revenue-authority HOW I WANT YOU TO ANSWER 1. Work from the legislation above. Read it before answering. Guidance from the Welsh Revenue Authority is its view of the law, not the law, and does not bind a tribunal or a court. 2. Tell me what the rule actually requires, in plain English. 3. Tell me which facts decide the answer, and which facts would change it. 4. Tell me what evidence I would need to support the position. 5. Be explicit about anything unsettled or fact-sensitive. Do not guess. 6. Your training data has a cutoff and SDLT rates and reliefs change at fiscal events. Say so if you are not sure the law is current. POINTS ALREADY KNOWN TO BE UNCERTAIN ON THIS TOPIC - The source does not explain what evidence the Welsh Revenue Authority will require for a power of attorney. - The source does not say whether permission covers every tax task or only selected matters. Do not give me a conclusion you cannot support from the provisions above.
Legislation links show the Land Transaction Tax and Anti-avoidance of Devolved Taxes (Wales) Act 2017 as it stood on 2025-11-17. The law may have changed since, and the rules that apply are those in force on the date of your transaction. The official guidance this page is based on is here.
This page was last updated on 3 September 2026
Useful article? You may find it helpful to read the original guidance here: Let someone deal with your LTT tax affairs
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